test(metrics): Fix the test on OpenShift for long namespace names

Author: siegfriedweber

tests/templates/kuttl/metrics/01-rbac.yaml

@@ -2,6 +2,16 @@
 apiVersion: kuttl.dev/v1beta1
 kind: TestStep
 commands:
-  - script: >
-      envsubst '$NAMESPACE' < 01_rbac.yaml |
-      kubectl apply -n $NAMESPACE -f -
+  - script: |
+      PROMETHEUS_HELM_RELEASE_NAME=prometheus-$NAMESPACE
+      PROMETHEUS_HELM_CHART_NAME=kube-prometheus-stack
+
+      # `kube-prometheus-stack.fullname` in the Prometheus Helm Chart is used to create the
+      # ServiceAccount names. It is set to `<.Release.Name>-<.Chart.Name>` and  truncated to
+      # 26 characters, see
+      # https://github.com/prometheus-community/helm-charts/blob/kube-prometheus-stack-81.2.2/charts/kube-prometheus-stack/templates/_helpers.tpl#L22
+      KUBE_PROMETHEUS_STACK_FULLNAME=$PROMETHEUS_HELM_RELEASE_NAME-$PROMETHEUS_HELM_CHART_NAME
+      export KUBE_PROMETHEUS_STACK_FULLNAME=${KUBE_PROMETHEUS_STACK_FULLNAME:0:26}
+
+      envsubst '$KUBE_PROMETHEUS_STACK_FULLNAME' < 01_rbac.yaml | \
+        kubectl apply --namespace=$NAMESPACE --filename=-

tests/templates/kuttl/metrics/01_rbac.yaml

@@ -18,8 +18,6 @@ rules:
     verbs:
       - use
 ---
-# `fullnameOverride` in the Prometheus Helm values must be set to `prometheus-$NAMESPACE`, so that
-# the ServiceAccounts are created with the names listed in this RoleBinding.
 kind: RoleBinding
 apiVersion: rbac.authorization.k8s.io/v1
 metadata:
@@ -28,11 +26,11 @@ subjects:
   - kind: ServiceAccount
     name: test-service-account
   - kind: ServiceAccount
-    name: prometheus-$NAMESPACE-admission
+    name: $KUBE_PROMETHEUS_STACK_FULLNAME-admission
   - kind: ServiceAccount
-    name: prometheus-$NAMESPACE-operator
+    name: $KUBE_PROMETHEUS_STACK_FULLNAME-operator
   - kind: ServiceAccount
-    name: prometheus-$NAMESPACE-prometheus
+    name: $KUBE_PROMETHEUS_STACK_FULLNAME-prometheus
 roleRef:
   apiGroup: rbac.authorization.k8s.io
   kind: Role

tests/templates/kuttl/metrics/10-install-prometheus.yaml

@@ -3,14 +3,13 @@ apiVersion: kuttl.dev/v1beta1
 kind: TestStep
 commands:
   # Append the namespace to the Helm release name so that cluster-wide resources get unique names.
-  # `fullnameOverride` is set to `prometheus-$NAMESPACE`, so that the ServiceAccounts are created
-  # with the names that are defined in `test-role-binding`.
-  - script: >
-      helm install prometheus-$NAMESPACE
-      --namespace $NAMESPACE
-      --version 80.14.2
-      --values 10_kube-prometheus-stack-values.yaml
-      --set fullnameOverride=prometheus-$NAMESPACE
-      --wait
-      oci://ghcr.io/prometheus-community/charts/kube-prometheus-stack
+  - script: |
+      PROMETHEUS_HELM_RELEASE_NAME=prometheus-$NAMESPACE
+
+      helm install $PROMETHEUS_HELM_RELEASE_NAME \
+        --namespace $NAMESPACE \
+        --version 81.2.2 \
+        --values 10_kube-prometheus-stack-values.yaml \
+        --wait \
+        oci://ghcr.io/prometheus-community/charts/kube-prometheus-stack
     timeout: 600